Thanks! Altho base time 6 hours shoots my "spirits tracking the spells back to source in mid battle" down the drain. It's hard to believe it would take so long in the astral - where people move a lot faster than in mundane space.

Perhaps, but the link is tenuous and Astral Space is a maze of links and impressions, signatures and sights. You must follow the line from where the spell stands to where the spell was cast through all the paths it travelled between and all the places the caster went following.

Besides, with an Intelligence of 6 and an Aura Reading of 6 you can expect 6 successes, or more. But, no, not a battle strategy.